As of 2025, it is illegal to marry your first cousin in Tennessee. In 2024, the Tennessee legislature passed a bill banning marriage between first cousins, and this law is now in effect.
The new statute prohibits marriage between “lineal descendants of a grandparent,” which includes first cousins.
This marks a significant change, as Tennessee had previously allowed first-cousin marriages due to a 1960 attorney general’s opinion that found no explicit prohibition in state law.
What Changed and Why
The push for the ban was driven by concerns over increased genetic risks for children born to first cousins, though some legislators argued these risks are not as high as commonly believed.
Attempts to allow cousin marriage with genetic counseling were rejected, and the final bill passed with overwhelming support in the state legislature.
How Tennessee Compares to Other States
With this change, Tennessee joins the majority of U.S. states that prohibit first-cousin marriages. As of early 2025, 24 states ban such unions outright, while 18 still allow them, and 8-including Tennessee-have specific restrictions or exceptions. Some states permit cousin marriage only under certain conditions, such as age or infertility.
Summary Table: First-Cousin Marriage in Tennessee (2025)
| Year | Legal Status | Details |
|---|---|---|
| 2023 | Legal | No explicit ban in state law |
| 2024 | Ban Enacted | Law passed, awaiting governor’s signature |
| 2025 | Illegal | First-cousin marriage now prohibited |
As of 2025, marrying your first cousin in Tennessee is illegal. This brings Tennessee in line with most other U.S. states, closing a legal loophole that had existed for decades.
Sources:
- https://en.wikipedia.org/wiki/Cousin_marriage_law_in_the_United_States
- https://www.newsweek.com/map-states-marry-cousin-tennessee-ban-1889727
- https://ifstudies.org/blog/why-every-state-should-ban-first-cousin-marriage
- https://newschannel9.com/newsletter-daily/tennessee-moves-to-ban-first-cousin-marriages-as-new-bill-heads-to-governors-desk